The development of hybrid vehicles and electric vehicles requires the application of efficient electrochemical energy stores. A sufficient performance is provided, for example, by lithium ion accumulators. However, the optimum power yield of lithium ion accumulators is temperature dependent. In fact, the temperature range in which lithium ion accumulators are able to be operated effectively and with certainty is the range from −10° C. to 50° C. This temperature range, however, is not sufficient for operation in a motor vehicle. Thus, it is also particularly desirable that a motor vehicle is also able to be operated in wintertime, when temperatures fall below −10° C. Temperatures of more than 50° C. may also occur in motor vehicles due to insulation. In this case, too, however, a secure operation of the lithium ion accumulator has to be ensured.
It is discussed in U.S. Pat. No. 3,110,633 that one may accommodate a sulfur-lead accumulator in a housing that is filled with a phase change material. The phase change material functions as a latent heat accumulator. The phase change material is used to store heat from the operation of the vehicle over a longer period, in order to improve cold start operation in response to shorter standstill times, in the case of outside temperatures below the freezing point, when the storage capacity of the lead-sulfur accumulator is greatly reduced. Such a sulfur-lead accumulator, as is used as a vehicle battery, is, however, not sufficient with respect to its power yield, for example, in order to actuate a hybrid vehicle or an electric vehicle.